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1.
For arbitrary interparticle interaction u(r12), the model two-electron atom in the title is shown to be such that the ground-state electron density ρ(r) is determined uniquely by the correlated kinetic energy density tR(r) of the relative motion. Explicit results for tR(r) are presented for the Hookean atom with force constant k=1/4, and also for . Possible relevance of the Hookean atom treatment to the ground state of the helium atom itself is briefly discussed.  相似文献   

2.
A.G. Ramm   《Physics letters. A》2007,370(5-6):522-527
A method is proposed to create materials with a desired refraction coefficient, possibly negative one. The method consists of embedding into a given material small particles. Given n0(x), the refraction coefficient of the original material in a bounded domain , and a desired refraction coefficient n(x), one calculates the number N(x) of small particles, to be embedded in D around a point xD per unit volume of D, in order that the resulting new material has refraction coefficient n(x).  相似文献   

3.
E. Momoniat   《Physics letters. A》2008,372(22):4041-4044
A Fourier point source solution modelling the effect of an impulse on a viscoelastic fluid of second-grade is investigated. By examining the second-moment of a Fourier point source solution we show that for Dt1, where D=ν/ for ν the kinematic viscosity, a viscoelastic parameter and t the time; the fluid undergoes superdiffusion indicating the dominance of the fluids viscoelastic properties. For Dt1 the fluid undergoes classical diffusion indicating that the viscous properties of the fluid are dominating.  相似文献   

4.
The six-dimensional Ising model with nearest-neighbor pair interactions is simulated on the Creutz cellular automaton by using the finite-size lattices with the linear dimensions L=4,6,8,10. The temperature variations and the finite-size scaling plots of the specific heat and Binder parameter verify the theoretically predicted expression near the infinite lattice critical temperature. The approximate values for the critical temperature of the infinite lattice TC=10.838(1), TC=10.836(20) and TC=10.835(1) are obtained from the intersection points of specific heat curves, Binder parameter curves and the straight line fit of specific heat maxima, respectively. These results are in agreement with the more precise value of TC=10.835(5). The value obtained for the critical exponent of the specific heat, i.e., =0.012(2) is also in agreement with =0 predicted by the theory.  相似文献   

5.
A correlated three-parameter variational ground-state Ψ(r1,r2,r12) proposed by Chandrasekhar for helium-like ions gives a high percentage of the electron correlation energy resulting from the interaction energy e2/r12 and also yields an analytic ground-state electron density ρ(r). Here, we extract via Schrödinger equation an exact Hamiltonian for which the Chandrasekhar wave function is the ground-state. Properties of the potential energy function in this Hamiltonian are quantified. Finally, kinetic energy densities are plotted and related to the Laplacian of ρ(r).  相似文献   

6.
In this Letter, the linear variable separation approach is successfully extended to (1+1)-dimensional Korteweg–de Vries (KdV) type models related to Schrödinger system. Some significant types of solitons such as compacton, peakon and loop solutions with periodic behavior are simultaneously derived from the (1+1)-dimensional soliton system by entrancing appropriate piecewise smooth functions and multivalued functions.  相似文献   

7.
We consider the implications from the possibility that the recently observed state X(3872) is a meson–antimeson molecule. We write an effective Lagrangian consistent with the heavy-quark and chiral symmetries needed to describe X(3872). We explore the consequences of the assumption that X(3872) is a molecular bound state of D*0 and mesons for the existence of bound states in the and channels.  相似文献   

8.
In this paper, we will define a quantum operator that performs the standard inversion about the mean only on a subspace of the system (Partial Diffusion Operator). This operator is used together with entanglement in a quantum search algorithm that runs in for searching an unstructured list of size N with M matches such that 1≤MN. We will show that the performance of the algorithm is more reliable than known fixed operators quantum search algorithms especially for multiple matches where we can get a solution after a single iteration with probability over 90% if the number of matches is approximately more than one-third of the search space. We will show that the algorithm will be able to handle the case where the number of matches M is unknown in advance in such that 1≤MN.  相似文献   

9.
The recent measurement by CDF M(Σb)−M(Λb)=192 MeV is in striking agreement with our theoretical prediction M(Σb)−M(Λb)=194 MeV. In addition, the measured splitting agrees well with the predicted splitting of 22 MeV. We point out the connection between these predictions and an effective supersymmetry between mesons and baryons related by replacing a light antiquark by a light diquark. We discuss the theoretical framework behind these predictions and use it to provide additional predictions for the masses of spin- and spin- baryons containing heavy quarks, as well as for magnetic moments of Λb and Λc.  相似文献   

10.
SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It is devoted to the search for intermediate mass magnetic monopoles (107–1013 GeV/c2) and nuclearites in the cosmic radiation using stacks of CR-39 and Makrofol nuclear track detectors. In four years of operation it will reach a sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of the calibration of CR-39 and Makrofol and the analysis of a first sample of the exposed detector.  相似文献   

11.
Recent progress of lower hybrid (LH) experiments with new graphite limiters configuration in the HT-7 tokamak is presented. The lower hybrid current drive (LHCD) efficiency can be determined by fitting based on experimental data. Improved particle confinement was observed via LHCD (PLHW>300 kW) characterized by the particle confinement time τp increased about 1.56 times. It is found that runaways are suppressed during loop voltage is decreasing at the flat-top phase of LH discharges. The main limitations of pulse length are presented in long-pulse experiments with new limiter configuration.  相似文献   

12.
A simple specific pattern of the two 3×3 quark mass matrices is proposed, resulting in a prediction of the CP phase of the charged-current mixing matrix VCKM, i.e., sin21(β)=0.733, which is in remarkable agreement with data, i.e., sin21=0.728±0.056±0.023 from Belle and sin2β=0.722±0.040±0.023 from BaBar. This pattern can be maintained by a discrete family symmetry, an example of which is D7, the symmetry group of the heptagon.  相似文献   

13.
Manu Mathur   《Physics letters. [Part B]》2006,640(5-6):292-296
We reformulate d-dimensional SU(2) lattice gauge theory in terms of gauge invariant loop state variables by solving the SU(2) Gauss law as well as the corresponding Mandelstam constraints. The loop states satisfying the Gauss law and the Mandelstam constraints in d dimension are explicitly constructed in terms of the SU(2) harmonic oscillator prepotential operators. We show that these mutually independent (orthonormal) loop states carry certain non-negative integer Abelian fluxes over the lattice links and are characterized by 3(d−1) gauge invariant angular momentum quantum numbers per lattice site. Thus, they provide a complete orthonormal loop basis in the physical Hilbert space of the gauge theory. Further, we derive the loop Hamiltonian and show that it counts, creates and annihilates the Abelian fluxes over the plaquettes. The generalization to SU(N) gauge group is discussed.  相似文献   

14.
We consider an impacting mechanical system in which a particle at position u(t) impacts with a periodically moving obstacle at position z(t), the motion of which is non-smooth. In particular we look at corner events when u impacts with z very close to a point where z loses smoothness. We show that this leads, through a corner bifurcation, to complex dynamics in u which can include periodic orbits of arbitrary period and period-adding cascades. By analysing associated maps close to the corner event, we show that this dynamics can be understood in terms of the iterations of a two-dimensional, piecewise linear, discontinuous map. We also show some links between this analysis and the difficult problem of understanding the motion of three objects which may have simultaneous impacts.  相似文献   

15.
We investigate the correlators of TrAμAν in matrix models on homogeneous spaces: S2 and S2×S2. Their expectation value is a good order parameter to measure the geometry of the space on which non-commutative gauge theory is realized. They also serve as the Wilson lines which carry the minimum momentum. We develop an efficient procedure to calculate them through 1PI diagrams. We determine the large N scaling behavior of the correlators. The order parameter shows that fuzzy S2×S2 acquires a 4-dimensional fractal structure in contrast to fuzzy S2. We also find that the two point functions exhibit logarithmic scaling violations.  相似文献   

16.
W. Weise  R. Hrtle 《Nuclear Physics A》2008,804(1-4):173-185
Recent developments are summarised concerning low-energy interactions as they relate to the possible existence of antikaon-nuclear quasibound states. An exploratory study of antikaons bound to finite nuclei is performed, with emphasis on the evolution of such states from light to heavy nuclei (A = 16–208). The energy dependent, driving attractive interactions are constructed using the s-wave coupled-channel amplitudes involving the Λ(1405) and resulting from chiral SU(3) dynamics, plus p-wave amplitudes dominated by the Σ(1385). Effects of Pauli and short-range correlations are discussed. The decay width induced by KNN two-body absorption is estimated and found to be substantial. It is concluded that -nuclear quasibound states can possibly exist with binding energies ranging from 60 to 100 MeV, but with short life times corresponding to decay widths of similar magnitudes.  相似文献   

17.
We calculate the wavelength dependence of the ratio of the linear polarization degree to extinction (polarizing efficiency) P(λ)/A(λ) from the ultraviolet to near-infrared. The prolate and oblate particles with aspect ratios from a/b=1.1 up to 10 are assumed to be rotating and partially aligned with the mechanism of paramagnetic relaxation (Davis–Greenstein). Size/shape/orientation effects are analyzed. It is found that the wavelength dependence of P(λ)/A(λ) is mainly determined by the particle composition and size whereas the values of P(λ)/A(λ) depend on the particle shape, degree and direction of alignment.  相似文献   

18.
The discrete subgroup Δ(27) of SU(3) has the interesting multiplication rule , which is used to obtain near tribimaximal neutrino mixing. Using present neutrino oscillation data as input, this model predicts that the effective mass mee measured in neutrinoless double beta decay will be 0.14 eV.  相似文献   

19.
Intense mechanoluminescent (ZnS)1−x(MnTe)x powder samples with x=0.02,0.05,0.10,0.15,0.20 and 0.25 were prepared by simple Solid State Reaction method. All samples were polycrystalline with wurtzite structure. Mechanoluminescence (ML) and Photoluminescence (PL) were observed in all the samples in the red region peaking around 650 nm. The red emission is attributed to the presence of Te along with Mn. ML is attributed to the release of holes due to the stress on the phosphors which then recombine with metastable Mn2+ emitting light. The intensity of ML is found to be strongly dependent on both the impact pressure and composition. The maximum intensities in both ML and PL were observed in samples with x=0.05.  相似文献   

20.
The current experimental determination of the absolute values of the CKM elements indicates that 2|Vub/VcbVus|=(1−z), with z given by z=0.19±0.14. This fact implies that irrespective of the form of the quark Yukawa matrices, the measured value of the SM CP phase β is approximately the maximum allowed by the measured absolute values of the CKM elements. This is for , which implies =π/2. Alternatively, assuming that β is exactly maximal and using the experimental measurement sin(2β)=0.726±0.037, the phase γ is predicted to be γ=(π/2−β)=66.3°±1.7°. The maximality of β, if confirmed by near-future experiments, may give us some clues as to the origin of CP violation.  相似文献   

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